More than 5000 entries on the history, culture and life of Britain (published in 1993 by Macmillan, now out of print)

Battle of the Atlantic

(1940–43)The long struggle of British and later American warships against the German U-boats, which threatened the convoys bringing crucial supplies from Canada and the USA in *World War II. The fall of France in June 1940 gave the U-boats Atlantic harbours from which they could raid far into the ocean. Large numbers of merchant ships were sunk that summer. The situation improved with the introduction of disciplined convoys (the U-boats responded by hunting in packs) and with the development of sonar (known at the time as asdic, an acronym of Anti-Submarine Detection Investigation Committee) and later of radar.

By the summer of 1943 the Allies had established control of the Atlantic. The conflict had included only one major surface encounter, when Germany's newest battleship, the Bismarck, ventured out in May 1941. She was sunk at the cost of the Hood, a British battle cruiser. Conditions in the Atlantic became familiar to a very wide post-war audience through the bestseller The *Cruel Sea.